Map constructor should fail if WebGL init fails.

[uforic]

Description

Currently, it's possible for the constructor to complete successfully but the painter not be defined.

This is because setupPainter doesn't throw an exception, but instead emits an ErrorEvent. The problem is that in the constructor() call, no listeners have been set up yet, so the user wouldn't be able to listen to this error and respond appropriately.

Later on, resize events cause the map to error, because painter.resize doesn't exist.

I'm open to suggestions, like:

• it's possible this is desired behavior
• right now, this would throw an error, and _setupPainter would emit an error event. we may want to dedupe this.
• this could actually be a bug in mapboxgl.isSupported(). We are checking this before instantiating the map, however, the _setupPainter call is still failing. Perhaps there are additional checks mapboxgl.isSupported should be making.

Keep me posted,
Thanks!

Error logs

Error seen on Sentry:
Cannot read property 'resize' of undefined

This is occurring in the constructor.

[uforic]

Update - the inability to create a painter causes an error later on in construction, it's just the wrong error; the error it later creates is:

Cannot read property 'resize' of undefined

From this code (in Sentry):

      const attemptedMap = new mapboxgl.Map({
        container: this.mapRef.current,
        style: this.getMapStyle(),
        center: initialCenter,
        zoom: initialZoom,
      });

Regardless, I'd argue we want to return the right error here (thrown from the right spot), not the wrong one.

[jfirebaugh]

Thanks! Fixes #2945.